The 4-momentum is tex2html_wrap127 where tex2html_wrap128 is the 4-velocity. Then: tex2html_wrap129 .

if tex2html_wrap130 , tex2html_wrap131 .

The 4-momentum is conserved. In an interaction of particles: tex2html_wrap132 .

tex2html_wrap133 . This means tex2html_wrap134 . So tex2html_wrap135 . This means: tex2html_wrap136 . Classically, this is: tex2html_wrap137 .


source psfile jl@crush.caltech.edu index
electromagnetic_force